COLORATION 135 



headed blackbirds, grackles generally, black and white 

 storks, oyster-catchers, black-bellied plovers, white egrets, 

 auks, puffins, guillemots, cormorants, orioles, tanagers, scar- 

 let ibises, flamingoes, vermilion and scissor-tailed fly- 

 catchers, and countless others, from the biggest to the 

 smallest, on land and on water, have highly advertising 

 colorations, and never gain any benefit from concealment. 

 Many of the smaller mammals, including the immense 

 majority of mice and shrews, lead their lives under such 

 circumstances as to make their diff^erent coloration pat- 

 terns of no consequence one way or the other in conceal- 

 ing them, and this although their prime hope of safety 

 from their foes lies in escaping observation. Habit and 

 cover are all-essential in their cases; and if their color- 

 ation in any case has been aff^ected by natural selection, 

 it has merely been done by setting wide limits, beyond 

 which coloration cannot transgress as regards advertising 

 quality. 



We wish to emphasize the fact that we are not now dis- 

 cussing the lower vertebrates and insects. From what we 

 have read it appears clear there are certain insects which 

 are protectively colored and which show that this is a sur- 

 vival factor by the care with which they light on objects 

 with which their coloration harmonizes. What is needed 

 to reach conclusions as regards these insects are such studies 

 as Doctor Henry Skinner's "Mimicry in Boreal American 

 Rhopalocera" {The Journal of the Academy of Natural 

 Sciences of Philadelphia, vol. XV, second series, March 21, 

 191 2). These studies make it evident that the extreme 

 positions taken in this matter by gentlemen like Professor 

 Poulton are not tenable. 



